1. Field of the Invention
The present invention relates to the field of lamp strings, such as a Christmas lamp string, and in particular to a lamp string that comprises a bulb socket that incorporates, in a removable manner, a plug carrying a current bypass device to provide current non-interruption for ensuring proper operation of the lamp string in case of broken bulbs.
2. The Related Arts
A lamp string, such as a Christmas lamp string, comprises a long string of sockets each receiving and holding a bulb, and such a long string of bulbs, when lit, is commonly used as decoration in for example holidays and festivals, especially in the nighttime. Some of the lamp strings use incandescent bulbs and a number of such bulbs are electrically connected in series to form a lamp string or a number of such lamp strings are connected together in parallel. The serial connection of bulbs in a lamp string is disadvantageous in that once one of the bulbs is broken or malfunctioning, the whole string fails, for the bulbs are set in serial connection.
To overcome such a problem, it is often provide a current bypass device, which can be in the form of for example a switching diode or a resistor. When one of the bulbs of a lamp string is broken, electrical current may bypass the broken bulb by flowing through the current bypass device to continuously supply power to the other bulbs of the lamp string, thereby maintaining normal light emission from the other bulbs.
To summarize, the conventional lamp string has the following drawbacks:
(1) For a conventional lamp string that contains no current bypass device, the whole lamp string may fail once one or more of the bulbs that constitute the lamp string are broken; and
(2) For a conventional lamp string that is provided with current bypass means, the assembling and repairing are difficult for no specific configuration or structure of the current bypass means is up-to-date known or available and further, it is not feasible for a lamp string manufacturer or general consumers to select if to install the current bypass means in the lamp string, and so is the modification of existing lamp string in this respect.
Thus, it is desired to provide a current bypass device for a lamp string to overcome the above problems.